Coal or rock drill.



.No.'683,|82. L. K. KODNTZ.

GOAL 0R ROCK DRILL.

(Application filed Mgr. 16, 1901. (N0 Model.)

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lmuumn I: nonnis PETERS co. pnoraumu, WASHINGTON n c INVENTORM off/6Patented Dec. 3, IQOIL UNTTED STATES PATENT OFFICE.

LOUIS K. KOONTZ, OF ALLEGHENY, PENNSYLVANIA.

COAL OR ROCK DRILL.

SPEGIFIGATIQIN formingpart of Letters Patent No. 688,182, dated December3, 1901. Application filed March 16, 1901. Serial No. 51,504. (Nomodel.)

T0 to whont it may concern:

Be it known that I, LOUIS K. KOONTZ,-a citizen of the UnitedStates,residingat Allegheny, in the county of Allegheny and State of Pennsylvania, have invented certain new and useful Improvements in Coal orRock Drills, of which the following is a specification, reference beinghad therein to the accompanying drawings.

This invention relates to coal and rock drills, and has particularreference to automatically-variable feed mechanism of simple andimproved construction for controlling the advance of the auger or drill.

The invention consists in the novel structural features and combinationof parts hereinafter fully described and claimed, and illustrated by theaccompanying drawings, where- 1n Figure 1 is a side elevation of adrillingmachine equipped with my improvement. Fig. 2 is a verticalcross-sectional view on line 2 2 of Fig. 1. Fig. 3 is a sectional planview. Fig. 4 is a detail view of one of the curved friction-plates.

Referring to the drawings, 2 represents the twist-drill, 3 the feed-bar,4 the crank, 5 the forked chair, and 6 the chair-supporting gripbar, allof usual and well-kn own construction.

7 is an internally-threaded head or nut through which feed-bar 3extends, and formed in the exterior face of this head is the continuousgroove or depression 8, the formation of said groove creating annularshoulders 9. Fitting loosely within this groove or depression of thehead are the two curved bearingplates 10. The plates are a little shortof being semicircular and are formed, preferably, of spring metal andnormally are of such form as to stand slightly away from the bottom ofgroove 8, as clearly shown in Fig. 2. The plates are formed on theirouter faces with the central depressions 11 to receive on one side theinwardly-projecting trunnion-nib 12 on one arm 5 of chair 5 and on theopposite side the trunnion screw 13, working in a threaded aperture inthe other chair-arm. The chair is of such size as to permit the feedheadto operate freely therein and to oscillate vertically on the horizontalaxis formed by the trunnions, thus providing for the difierent operativepositions necessary in this class of machinery.

In operation screw 13 is so adjusted as to cause the plate extremities10' to frictionally engage the head with more or less force and resistrotation of the head with the feed-bar. If the resistance of the augeris sulficient to overcome the resistance of plates 10, the head willrotate with the feed-bar and the auger will simply rotate withoutadvancing. On the other hand, if the tension of the plates 10 issufficient to hold head 7 stationary notwithstanding the resistance ofthe drill the feedbar will advance therethrough and create a positivefeed for the auger. Under ordinary working conditions the adjustment bymeans of screw 13 is such that the opposing resistances are about evenlybalanced, with the result that nut 9 rotates between plates 10, but at aslower speed than the feed-bar and auger. However, this may be arrangedas circumstances may require-as, for instance, if working incomparatively soft material and a rapid feed is desirable the tension ofplates 10 may be so increased as to hold the head fixed.

The plates 10 not only regulate the feed, but also support head 7 withinchair 5 and hold the head against longitudinal movement in eitherdirection. As above stated, the plates 10 are preferably of spring metaland normally have slightly-sharper curvatures than the face of the head7, which they impinge. Said plates may, however, be curvedconcentrically with the head-surface against which they bear andnormally impinge the same their entire length and the tension beregulated by screw 13 alone and unaided by the spring function of theplates. The construction just described would be exactly the same inappearance as the mechanism here shown would present under an extremeadjustment which would force the entire length oflthe plates against thehead.

Plates 10 may be used interchangeably, and the support which theyconstitute may be used reversely or with either face toward the coal.Instead of the rib-support 6a vertical post may be employed, and crank 4may be displaced by a ratchet-lever, all of which are well-knownequivalents in the art.

While myimproved automatically-variable feed-head is here shown anddescribed in connection with a threaded feed-bar, I do not restrictmyself to its use in connection with such bar, as it may be soconstructed as to operate directly on the spiral or twist auger withoutdeparting from the, spirit or scope of the invention.

Having thus fully described my invention, what I claim as new, anddesire to secure by Letters Patent, is-

1. The combination of oppositely-arranged trunnion-supports, anauger-feeding head, and oppositely-curved plates embracing the head andsupporting the same against vertical and longitudinal displacement,tl1ecurved plate having pivotal connection with the tru nnion-supports, andmeans for varying the frictional engagement of the curved plates withthe head, substantially as shown and described.

2. The combination of oppositely-arranged trunnion-supports adjustablewith relation to each other, an auger-feeding head having a continuousgroove in its exterior, and oppositely-facing curved plates Within theheadgroove, the plates being engaged and sustained by theoppositely-arranged trunnionsupports, thereby holding the said head inoperative position, substantially as shown and described.

3. The combination of a rotatabie augerfeeding head having a continuousgroove in its exteriormon-rotatable curved spring-plates lying inopposite sides of the said groove and frictionally engaging the bottomthereof, said plates having slightlysharper curvature than thegroove-bottom, and means for contracting said plates and increasingtheir frictional engagement with the head, substantially as shown anddescribed.

4. The combination of a forked chair, an inwardly-projectingtrunnion-nib on one of the chair-arms, a trunnion-screw adjustablethrough the opposite chair-arm, a rotatable auger-feeding head having acontinuous peripheral groove, and curved plates lying in said groove andformed With depressions on their outer faces to receive the saidtrunnionnib and trunnion -screw, substantially as shown and described.

In testimony whereof I affix my signature in presence of two Witnesses.

LOUIS K. KOONTZ.

Witnesses:

J. M. NESBIT, ALEX. S. MABON.

